| 摘要 |
1,163,553. Maps. INTERNATIONAL STANDARD ELECTRIC CORP. 30 Sept., 1966 [4 Oct., 1965], No. 11782/69. Divided out of 1,163,552. Addition to 1,066,008. Heading G5G. [Also in Division G2] In an optical projection system for use in navigational situation display, images from an axially and rotatably movable cylindrical map transparency 1 are projected by lens 35 and prism 36 on to screen 25 in superposition with images projected from cathode-ray tube 26 by lens 28, prism 36 being located at the exit pupil of lens 35 and within the exit cone of light from lens 28. The map projection system is optically folded and is located within the transparency cylinder, a Dove prism in the system rotating the projected map image according to aircraft heading. Prism 36 is suspended by wires attached to ring 46 and may comprise two cemented prisms with a small reflecting spot on their hypotenuse interface. |
